two almost identical e-mail messages, one is classified as spam

Can you tell me what goes wrong? I have two almost identical e-mail messages, one is classified as spam with a ANY_BOUNCE_MESSAGE and a BOUNCE_MESSAGE score of 10. The other message is not classified as spam.

Both e-mails are send from the same server. I have attached the headers and spam scores at this ticket.

Thanks in advance,

Reply:

The two messages are almost identical, as you said, but they are not the same, and this makes the difference. The difference is in the message size, and above a certain size messages are not scanned. You can change this in the Anti Spam - Setup, in the Basic section.